The invention relates to identifying devices on a network.
With the large number of computing devices which can be connected to a network (made up of local area networks or LANs and wide area networks or WANs), various methods have been developed to identify and manage the network devices to enable communication among them. Typically, a network directory service, which is essentially a catalog or directory of names and addresses of network devices (such as servers, hubs, desktops, laptops, and other devices), is maintained on selected network devices. Devices within a LAN usually have their own route tables of other devices in the LAN to allow quick and efficient communication within the LAN. However, should a LAN device desire to communicate with a device outside the LAN, then the directory stored on a selected network device is accessed to determine the appropriate address of the target.
Methods of identifying computing devices on a network include exhaustive pinging and route table scanning. Both of these methods are implemented in the Open View network management product sold by Hewlett-Packard Company. In exhaustive pinging, selected servers on a network send out query packets for all addresses in a specified range. If a response is obtained for a particular address in the form of a packet, then the name and address of the responding device are added to a directory or catalog.
In route table scanning, used by networks implementing the Simple Network Management Protocol (SNMP), network devices determine the gateway systems on the network to access their route tables. The route tables contain the names and addresses of devices known to the gateway servers. The route table scanning method also accesses route tables of other known routers to determine devices that have routed through those routers. In this manner, a substantial portion of devices on the network can be identified.
In both the pinging and route table scanning methods, a large number of query packets are issued to identify network devices.